Method and apparatus of adhering belt edge tape

ABSTRACT

Adhering a belt edge tape to both respective side edge portions of the belt on the outer peripheral surface of the building drum by supplying a belt edge tape toward the outer peripheral surface of the building drum by pressing using an extruder which constitutes a supply device facing the building drum in an opposed manner and by pressing the tape to the building drum using a press roller on a leading side as viewed from a position where the tape is supplied in the rotational direction of the building drum, the building drum is rotated in the direction that end portions of the reinforcing cords on the side edge portion of the belt which constitutes a tape adhering side are positioned on a trailing side in the rotational direction of the building drum thus adhering the tape to the side edge portion.

TECHNICAL FIELD

The present invention relates to a method and an apparatus of adheringbelt edge tapes in tire building.

BACKGROUND ART

In general, the tire (mainly vehicle-use tire) T is constituted of aplurality of rubber members and a plurality of reinforcing members,wherein the reinforcing members are mainly formed of cords. As a typicalexample, as shown in FIG. 10, the tire T is formed by combining therubber members such as an inner liner 2, a tread 3, side walls 4, rimstrips or chafers 5 with a carcass layer 6 and a belt layer 7constituting a reinforcing member including cords, a bead body 8consisting of bead cores 8 a and bead fillers 8 b. FIG. 9 shows oneexample of respective constitutional members of the tire in an explodedmanner.

The belt layer 7 is formed of a belt member in which a large number ofreinforcing cords mainly made of metal is embedded in a rubber materialin parallel to each other. The cords are arranged in an inclinationdirection at a predetermined angle with respect to the circumferentialdirection of the tire. Usually, the belt layer 7 is formed of a plurallayers of belts 7 a, 7 b having different widths which are stacked withthe respective inclination directions arranged opposite to each other.In general, the belt 7 a which constitutes a lower layer (a first layer)has a width larger than a width of the belt 7 b which constitutes anupper layer (a second layer). Although not shown in FIG. 10, areinforcing layer 9 formed by a spirally-wound ribbon containingsynthetic resin cords therein is formed on the belt layer 7.

For the purpose of protecting side edge portions of both belts 7 a, 7 band for preventing the occurrence of a defect such as separation,so-called belt edge tapes 1 made of a rubber member which play a role ofcushion rubber are interposed between both side end portions of thebelts 7 a, 7 b. Further, when necessary, at a position inwardly fromboth side end portions of the belts 7 a, 7 b, an inter-belt pad (omittedfrom the drawing) which constitutes a buffer member for shearing straingenerated between belts is interposed between both belts 7 a, 7 b.

Conventionally, in a step different from a tire building step, the beltis manufactured and the belt edge tapes 1 are adhered to themanufactured belt. Recently, there has been proposed adhesion buildingin which a belt is manufactured at a position where the belt faces abuilding drum in an opposed manner in the adhesion step during tirebuilding and the manufactured belt is supplied to the building drum tothe building drum while the belt is being manufactured. Along with suchadhesion building, the belt edge tapes 1 and the inter-belt pad are alsoadhered in a step after the belt 7 a which constitutes the lower layeris adhered. The belt edge tapes 1 also functions as the inter-belt pad.

In adhering the belt edge tape 1, mainly, an unvulcanized rubber memberis extruded in a tape shape having a predetermined width and apredetermined thickness by an extruder along with the rotation of thebuilding drum, and extruded belt edge tape 1 is adhered to a side edgeportion of the belt 7 a by pressing the belt edge tape 1 using the pressroller.

Here, in view of the configuration of a belt member, particularly inview of the configuration of the side edge portion where the inclinedbonding ends and ends of the reinforcing cords in the inclinationdirection are present in manufacture, depending on the rotationaldirection of the building drum, the press rollers rub against the beltand hence, the press roller is caught by the bonding ends or the ends ofthe reinforcing cords whereby the belt edge tape made of the rubbermaterial may be broken. Accordingly, there may be a case where the beltedge tape cannot be pressed smoothly.

That is, the belt member is manufactured as follows. A strip-shapedmaterial having a predetermined width and containing reinforcing cordsextending in the longitudinal direction is cut obliquely at apredetermined angle (usually approximately 20°) corresponding to a cordangle of the belt layer with a length corresponding to the belt width,and fine-strip-shaped belt member pieces acquired by cutting have sidesthereof bonded to each other such that cut ends are aligned to form bothside edges of the belt member thus producing belt members having alength amounting to one circumference of a tire or elongated belt member(see patent document 1 and patent document 2, for example).

Due to such a constitution, on the side edge portion of the belt member,as illustrated in FIG. 8, cut ends of the reinforcing cords C arrangedin the inclination direction are exposed and, at the same time, inclinedbonding ends of a large number of fine-strip-shaped belt member pieces bare also present. Further, an acute-angled distal end b1 is present dueto the inclination of the fine-strip-shaped belt member piece b.Depending on a bonding state, the above-mentioned distal end b1 may beslightly warped or formed in a projecting manner.

Accordingly, in adhering the belt edge tape to the side edge portion ofthe belt, when the adhesion is performed by rotating the building drumalways in the same direction, on either one side edge portion, the pressroller adheres the belt edge tape by pushing the inclined ends of thereinforcing cords and the acute-angled distal ends of the inclined beltmember pieces in the direction that the press roller rubs against suchends of the reinforcing cords and the distal ends. Eventually, the endsof the reinforcing cords or the distal ends are caught by the pressroller and hence, the press roller cannot perform smooth pressingwhereby the belt edge tape is broken or a pressing force becomesinsufficient.

-   Patent document 1: JP-A-11-99564-   Patent document 2: JP-A-2000-280373

DISCLOSURE OF THE INVENTION Problems that the Invention is to Solve

The present invention has been made to overcome the above-mentioneddrawbacks, and it is an object of the present invention to provide anadhesion method and an apparatus of the belt edge tape which can, inbuilding a tire, facilitate the adhesion of a belt edge tape made of arubber material interposed between side end portions of belt layers, andsmoothly and surely adhere the belt edge tape by pressing using pressrollers while preventing cords end or acute-angled distal ends offine-stripe-shaped belt member pieces arranged in the inclinationdirection from being caught by the press rollers thus enhancing theadhering accuracy of the belt edge tape.

Means for Solving the Problems

The present invention is directed to a method of adhering belt edgetapes made of a rubber material which are interposed between a pluralityof belts containing inclined reinforcing cords therein to side edgeportions of a belt adhered to an outer peripheral surface of a buildingdrum during one step of tire building, wherein in adhering the belt edgetape to both respective side edge portions of belt on the outerperipheral surface of the building drum by supplying the belt edge tapetoward the outer peripheral surface of the building drum along with therotation of the building drum by a supply device which faces thebuilding drum in an opposed manner and by pressing the belt edge tape tothe building drum using a press roller on a leading side as viewed froma position where the belt edge tape is supplied in the rotationaldirection of the building drum along with the supplying of the belt edgetape, the building drum is rotated in the direction that end portions ofthe reinforcing cords on the side edge portion of the belt whichconstitutes a tape adhering side are positioned on a trailing side inthe rotational direction of the building drum thus adhering the beltedge tape to the side edge portion.

According to the above-mentioned method, in adhering the belt edge tapeto both side edge portions of the belt, on either side of both side edgeportions, the building drum is rotated in the direction that endportions of the reinforcing cords at the side edge portion arepositioned on a trailing side in the rotational direction of thebuilding drum. Accordingly, there is no possibility that the pressroller rubs against the end portions of the inclined cords or theacute-angled distal ends of the inclined belt member pieces and hence,it is possible to surely and smoothly adhere the belt edge tape whilepressing the belt edge tape in the inclination flowing direction.

As the supply device, an extruder which extrudes the belt edge tapehaving a predetermined cross-sectional shape toward the building drummay preferably be used. Due to such constitution, it is possible tosmoothly adhere the belt edge tape made of an unvulcanized rubbermaterial to the side edge portion of the belt while extruding the beltedge tape as described above. Particularly, by suitably setting across-sectional shape of the belt edge tape extruded from the extruder,the tape can be also used as inter-belt pads thus omitting conventionalinter-belt pads.

In the method of adhering belt edge tapes, the belt may preferably beformed of a belt member which is obtained by obliquely cutting abelt-use strip-shaped material made of a rubber material in which aplurality of reinforcing cords is embedded in parallel to each other andby arranging and bonding a large number of fine-strip-shaped belt memberpieces which are formed by cutting in a state that the cords arearranged in the inclination direction, in adhering the belt edge tape toboth respective side edge portions of the belt adhered to the buildingdrum, the building drum may preferably be rotated in the direction thatend portions of the belt member pieces at the side edge portion of thebelt which constitutes a tape adhering side are positioned on a trailingside in the rotational direction of the building drum.

Due to such constitution, in the manufacture of the belt, also on theside edge portion of the belt where the fine-strip-shaped belt memberpieces obtained by obliquely cutting the elongated strip-shaped materialare arranged and bonded to each other, there is no possibility that thepress rollers rub against acute-angled distal ends formed by obliquecutting and hence, the belt edge tape can be adhered without making thepress rollers caught by the acute-angled distal ends at the time ofpressing the belt edge tape using the press rollers.

Further, the present invention is directed to an apparatus of adheringbelt edge tapes made of a rubber material which are interposed between aplurality of layers of belts containing inclined reinforcing cordstherein to both side edge portions of a belt adhered to an outerperipheral surface of a building drum during of the belt tire building,wherein the apparatus includes a supply device which faces the buildingdrum capable of being rotated in the forward and reverse directions inan opposed manner and supplies the belt edge tape toward the outerperipheral surface of the building drum along with the rotation of thebuilding drum, a pair of upper and lower press rollers capable ofperforming a pressing operation respectively is mounted on upper andlower portions of the supply device such that the press rollers areallowed to press the belt edge tape to the outer peripheral surface ofthe building drum, the upper and lower press rollers are arranged suchthat the press rollers press the belt edge tape on a leading side in therotational direction of the building drum along with the forward orreverse rotation of the building drum.

Due to such constitution, with respect to one side edge portion of thebelt and another side edge portion of the belt which constitute thelower layers adhered to the outer peripheral surface of the buildingdrum, by setting the rotational directions of the building drum oppositeto each other, on either one of the side edge portions, the buildingdrum is rotated in the direction that the end portions of thereinforcing cords on the side edge portion are positioned on a trailingside in the rotational direction of the building drum, the belt edgetape is adhered to the end portions of the reinforcing cords along withthe rotation and hence, the belt edge tape is adhered by pressing usingthe press rollers on the leading side in the rotational direction of thebuilding drum. Accordingly, even if the acute-angled distal ends of thefine-strip-shaped belt member pieces present on the side edge portion ofthe belt are warped state, there is no possibility that the pressrollers are caught by the acute-angled distal ends and hence, the beltedge tape can be smoothly and surely adhered by pressing using therollers whereby the above-mentioned method can be favorably carried out.

In the apparatus of adhering belt edge tapes, the supply device maypreferably be an extruder which extrudes the belt edge tape having apredetermined cross-sectional shape toward the building drum, and thepair of upper and lower press rollers may preferably be mounted on ahead portion of the extruder. Due to such constitution, the belt edgetape made of an unvulcanized rubber material can be smoothly adhered tothe side edge portion of the belt while extruding the belt edge tape asdescribed above.

In the apparatus of adhering belt edge tapes, the building drum iscontrolled to be rotated in the direction that end portions of the cordsat the side edge portion of the belt which constitutes a tape adheringside of the belt adhered to the outer peripheral surface of the buildingdrum are positioned on a trailing side in the rotational direction ofthe building drum. Due to such constitution, on the above-mentioned bothrespective side edge portions of the belt, it is possible to adhere thebelt edge tape to by rotating the building drum such that the endportions of the reinforcing cords on the side edge portion whichconstitutes a tape adhering side are positioned on a trailing side inthe rotational direction of the building drum.

Further, in the apparatus of adhering belt edge tapes, the building drumis capable of moving relative to the supply device in the drum widthwisedirection to allow the supply device to be positioned to face one sideor another side of the both side edge portions of the belt adhered tothe outer peripheral surface of the building drum in an opposed mannerthus adhering the belt edge tape to the belt. Due to such constitution,the adhesion of the belt edge tape at both side edge portions of thebelt can be performed without any problems.

In the apparatus of adhering belt edge tapes, the pair of upper andlower press rollers may preferably be supported on the head portion ofthe supply device in a state that the press rollers are tiltable in thepressing direction and the press rollers may be configured toalternately perform a pressing operation using a press drive means. Dueto such constitution, the above-mentioned method can be favorablycarried out.

Advantage of the Invention

According to the method and the apparatus of adhering a belt edge tapeof the present invention, the belt edge tape interposed between theplurality of belt layers can be adhered to both respective side edgeportions of the belt adhered to the building drum such that the buildingdrum is rotated in the directions opposite to each other at both sideedge portions in the direction that the end portions of the reinforcingcords at the side edge portion are positioned on a trailing side in therotational direction of the building drum, and the belt edge tape isadhered by pressing using the press rollers on the leading side in therotational direction of the building drum. Accordingly, on the side edgeportion of the belt, the ends of the reinforcing cords or theacute-angled distal ends of the fine-strip-shaped belt member pieceswhich constitute the belt member are directed toward the trailing sidein the rotational direction of the building drum and hence, the pressrollers do not rub against the ends of the reinforcing cords or theacute-angled distal ends whereby the favorable pressing state can beensured without making the press rollers caught by the ends of thereinforcing cords or the acute-angled distal ends thus bringing aboutthe favorable adhesion of the belt edge tape.

BEST MODE FOR CARRYING OUT THE INVENTION

Next, a mode for carrying out the present invention is explained basedon an embodiment shown in drawings.

FIG. 1 is a schematic plan view of a portion of a step of adhering abelt edge tape in a tire building step,

FIG. 2 is an enlarged plan view showing the positional relationshipbetween a building drum and an extruder in the tire building step, and

FIG. 3 is an enlarged side view of the building drum and the extruder.

FIG. 4 is a partial side view of an adhering state of the belt edge tapeat one side edge portion of a belt,

FIG. 5 is a partial perspective view of an adhering state of the beltedge tape at one side edge portion of the belt,

FIG. 6 is a partial side view of an adhering state of the belt edge tapeat another side edge portion of the belt, and

FIG. 7 is an explanatory plan view when the belt edge tape is adhered tothe side edge portion of the belt.

In the drawings, a symbol D indicates an expansible/shrinkable buildingdrum for building a cylindrical-shaped belt band formed of a belt layer7 which is constituted of a plurality of belts 7 a, 7 b. The buildingdrum D is supported on a support base E for moving the building drum Dsuch that the building drum D is rotatably driven. The building drum Dis conveyed from a position P1 for adhering and building a belt 7 awhich constitutes a lower layer (a first layer) out of the plurality ofbelts 7 a and 7 b to a position P2 for adhering the belt edge tape 1.The building drum D is configured to move and stop at a position whereone side edge portion of the lower-layer belt 7 a on an outer peripheralsurface of the building drum D faces an extruder described later in anopposed manner and at a position where another side edge portion of thelower-layer belt 7 a on the outer peripheral surface of the buildingdrum D faces the extruder in an opposed manner. Besides theabove-mentioned constitution, the extruder may be configured to berelatively movable in the drum width direction.

In the drawings, symbol 10 indicates the extruder which constitutes asupply device for supplying the belt edge tape to be adhered to bothside edge portions of the lower-layer belt 7 a adhered to the outerperipheral surface of the building drum D at the adhering position P2,that is, a belt edge tape 1 made of an unvulcanized rubber material. Thesupply device may be formed of a device other than the extruder 10. Forexample, the supply device may be formed of a device which winds a beltedge tape extruded in a tape shape having a predetermined width and apredetermined thickness around a reel or the like in other step andunwinds and pulls out the belt edge tape. However, in this embodiment,the explanation is made with respect to a case in which the extruder 10arranged to face the building drum D in an opposed manner extrudes thebelt edge tape 1 toward an outer peripheral surface of the building drumD and adheres by pressing the belt edge tape 1 to the outer peripheralsurface of the building drum D.

In the extruder 10 shown in the drawing, a body portion 11 is mounted ona moving means 20 so that the extruder 10 is movable in the directiontoward or away from the building drum D which is placed at the adheringposition P2. In adhering the belt edge tape 1 to the building drum D,the extruder 10 is configured to approach and reach a position where apredetermined distance suitable for adhesion is defined between theextruder 10 and the outer peripheral surface of the building drum D.Further, the approaching position can be adjusted corresponding to thediameter of the building drum D.

The extruder 10 includes a screw shaft (not shown in the drawings) forextruding the belt edge tape 1 in the inside of the body portion 11thereof, and the extruder 10 also mounts a gear pump (not shown in thedrawings) and a die 13 for forming the belt edge tape 1 having across-sectional shape of predetermined width and thickness thereon. Whenthe belt edge tape 1 also functions as an inter-belt pad, a die 13 whichcan extrude the belt edge tape 1 of a width and a thicknesscorresponding to the inter-belt pad is used. An extruding operation bythe extruder 10 is controlled by a controller (not shown in thedrawings) such that the belt edge tape 1 is extruded at a speedcorresponding to the rotation of the building drum D. Symbol 14indicates a drive motor of the gear pump.

A pair of upper and lower press rollers 15 a, 15 b is mounted on upperand lower portions of the head portion 12. These press rollers 15 a, 15b are provided for pressing the belt edge tape 1 made of theunvulcanized rubber material and extruded from the die 13 to the outerperipheral surface of the building drum D on a leading side in therotational direction of the building drum corresponding to therotational direction of the building drum D.

The upper and lower press rollers is tiltably supported on the headportion 12 in the pressing operation direction by way of arm members 16a, 16 b and, at the same time, are configured to perform the pressingoperation alternately or arbitrarily by properly operating pressingdrive means 17 a, 17 b. Particularly, corresponding to the rotation ofthe building drum D, the extruder 10 is operated so as to extrude thebelt edge tape 1 and, at the same time, the upper and lower pressrollers 15 a, 15 b are operated such that the press roller which ispositioned on a leading side in the rotational direction of the buildingdrum D performs the pressing operation corresponding to the rotationaldirection of the building drum D.

That is, when the building drum D is rotated in the upward direction ona side where the building drum D faces the extruder 10 in an opposedmanner, as shown in FIG. 4 and FIG. 5, the upper and lower press rollers15 a, 15 b are set such that the lower press roller 15 b assumes anon-pressing state and the upper press roller 15 a performs the pressingoperation. On the other hand, when the building drum D is rotated in thedownward direction on the side where the building drum D faces theextruder 10 in an opposed manner, as shown in FIG. 6, the upper andlower press rollers 15 a, 15 b are set such that the upper press roller15 a assumes a non-pressing state and the lower press roller 15 bperform the pressing operation.

The pair of press rollers 15 a, 15 b may be configured to perform thepressing operation alternately by operating one pressing drive means ormay be configured to individually perform the pressing operation byoperating separate pressing drive means.

Further, the rotational direction of the building drum D is controlledsuch that corresponding to the inclination direction of the reinforcingcords C in the lower-layer belt 7 a adhered to the outer peripheralsurface of the drum, the building drum D is rotated in the directionthat end portions of the reinforcing cords at the side edge portion ofthe belt which constitutes a tape adhering side are positioned on atrailing side in the rotational direction of the building drum D.

That is, the building drum D is set and controlled as shown in FIG. 7.That is, when a left side edge portion of the belt 7 a on the outerperipheral surface of the building drum D is a tape adhering side andthe cords is inclined in the right upward inclination direction, thebuilding drum D is rotated in the upward direction (in the directionindicated by a solid-line arrow). On the other hand, when a right-sideside edge portion of the belt 7 a on the outer peripheral surface of thebuilding drum D is a tape adhering side and the cords is inclined in theleft downward inclination direction, the building drum D is rotated inthe downward direction (in the direction indicated by a dotted-linearrow). Then, corresponding to the rotational direction of the buildingdrum D, the pressing operations of the press rollers 15 a, 15 b arecontrolled in the above-mentioned manner.

In adhering the belt edge tape 1 made of the unvulcanized rubbermaterial to the side edge portion of the lower-layer belt 7 a on thebuilding drum D using the above-mentioned apparatus of adhering the beltedge tape 1, in a state that the one side edge portion is positioned toface the extruder 10 in an opposed manner, the head portion 12 of theextruder 10 is made to approach and reach a position where apredetermined distance is held between the head portion 12 of theextruder 10 and the belt 7 a on the building drum D. In this state, thebuilding drum D is rotated in the direction that end portions of thereinforcing cords on the side edge portion of the belt are positioned ona trailing side in the rotational direction of the building drum D (inthe direction indicated by the solid-line arrow in FIG. 7), and the beltedge tape 1 having the predetermined cross-sectional shape and made ofthe rubber material is extruded by operating the extruder 10corresponding to the rotation of the building drum D. Simultaneous withsuch an extruding operation, the upper press roller 15 a performs thepressing operation so as to adhere the belt edge tape 1 to one side edgeportion (left side edge portion shown in FIG. 7) of the belt 7 a.

When the adhesion of the one belt edge tape 1 amounting to one turn ofthe building drum D is completed, the operation of the extruder 10 isstopped to stop extrusion and the rotation of the building drum D iscontinued in a state that the belt edge tape 1 is pressed by the pressroller 15 a and hence, the belt edge tape is cut by tearing. Thereafter,a pressing force applied to the belt edge tape 1 by the press roller 15a is released.

Then, the building drum is moved in the width direction, and anotherside edge portion is positioned to face the extruder 10 in an opposedmanner. In such a state, the building drum D is rotated in the directionopposite to the rotational direction of the building drum D on theabove-mentioned one side, that is, in the downward direction (thedirection indicated by the dotted arrow in FIG. 7) such that the endportions of the inclined reinforcing cords of on the side edge portionare positioned on a trailing side in the rotational direction of thebuilding drum D. Corresponding to this rotation, the extruder 10 isoperated so as to extrude the belt edge tape 1 made of the rubbermaterial and, simultaneously, the lower press roller 15 b is operated toperform a pressing operation thus adhering by pressing the belt edgetape 1 to another side edge portion of the belt 7 a. Upon completion ofadhesion of the belt edge tape 1 amounting to at least one turn of thebuilding drum D, the belt edge tape 1 is cut in the same manner asmentioned previously and, thereafter, the pressing of the press roller15 b is released, and the whole extruder 10 is retracted to a standbyposition.

After completion of the adhesion of the belt edge tape 1, theabove-mentioned building drum D is moved to an adhesion buildingposition (not shown in the drawing) of the belt 7 b which constitutesthe upper layer (second layer). With the adhesion building of the belt 7b, the belt edge tape 1 is interposed between the side edge portions ofthe belts 7 a, 7 b which constitute the lower and upper layersrespectively.

With respect to inter-belt pads, depending on necessity, the inter-beltpads may be interposed between belts by adhesion separate from theadhesion of the belt edge tape 1, or the belt edge tape 1 may beconfigured to also function as the inter-belt pads, or the adhesion ofthe inter-belt pads may be omitted.

As described above, in adhering the belt edge tape 1 to both respectiveside edge portions of the belt 7 a which constitutes the lower belt, thebuilding drum D is rotated in the direction that the end portions of thereinforcing cords at the belt side edge portion of the belt whichconstitutes a tape adhering side are positioned on a trailing side inthe rotational direction of the building drum D, and the belt edge tape1 is adhered by pressing to the belt 7 a by the press roller 15 a or 15b on a leading side in the rotational direction and hence, on the beltedge portion, the ends of the reinforcing cords and the acute-angleddistal ends b1 of the fine-strip-shaped belt member pieces b whichconstitutes the belt member are directed toward the trailing side in therotational direction of the building drum D. Accordingly, there is nopossibility that the press roller 15 a, 15 b rubs against the inclinedends of the reinforcing cords or the acute-angled distal ends of theinclined strip-shaped belt member pieces and hence, even if theacute-angled distal ends b1 of the belt member pieces are projected in aslightly warped manner, there is no possibility that the pressingrollers 15 a, 15 b are caught by the ends of the reinforcing cords orthe acute-angled distal ends b1 or the belt edge tape 1 is broken andhence, the belt edge tape 1 can be approximately uniformly and surelypressed to the whole circumference of the tire whereby the belt edgetape 1 can be smoothly and accurately adhered to the belt 7 a.

Particularly, with the use of the apparatus which mounts the pair ofupper and lower press rollers 15 a, 15 b on the head portion 12 of theabove-mentioned extruder 10 and controls the pressing corresponding tothe rotational direction of the building drum D and hence, theabove-mentioned adhesion of the belt edge tape 1 can be easily andautomatically performed.

Here, even when the belt layer has the three-layered structure having abuffer belt as the innermost layer (first layer) besides theabove-mentioned two-layered belt as in the case of a heavy-duty tiresuch as a track or a bus, the present invention is applicable, in thesame manner as describe above, by interposing the belt edge tape betweena belt which constitutes the intermediate layer (second layer) havingthe largest width and a belt which constitutes the third layer arrangedabove the intermediate layer. Here, the inter-belt pads are interposedbetween the belt which constitutes the innermost layer and theintermediate layer.

INDUSTRIAL APPLICABILITY

The method and apparatus of adhering the belt edge tape of the presentinvention are, in some parts of the building step of the tire having aplurality of layers, preferably applicable to the adhesion of the beltedge tape made of a rubber material which is interposed between the beltlayers for protecting the belt edge or preventing the separation defect.Further, the method and apparatus of adhering the belt edge tape of thepresent invention are also applicable to the adhesion of the belt edgetape which also functions as the inter-belt pads.

BRIEF DESCRIPTION OF THE DRAWINGS

[FIG. 1] A schematic plan view of a portion of a step of adhering a beltedge tape in a tire building step illustrating one embodiment of theinvention.

[FIG. 2] An enlarged plan view showing the positional relationshipbetween a building drum and an extruder in the tire building step.

[FIG. 3] An enlarged side view showing the head portion of the extruder.

[FIG. 4] A partial side view of an adhering state of the belt edge tapeat one side edge portion of a belt layer.

[FIG. 5] A partial perspective view of an adhering state of the beltedge tape at one side edge portion of a belt layer.

[FIG. 6] A partial side view of an adhering state of the belt edge tapeat another side edge portion of the belt layer.

[FIG. 7] An explanatory plan view when the belt edge tape is adhered tothe side edge portion of the belt layer.

[FIG. 8] An enlarged explanatory view of one side edge portion of thebelt layer.

[FIG. 9] A schematic explanatory view showing one example of respectiveconstitutional parts of a tire in an exploded manner.

[FIG. 10] A cross-sectional explanatory view of the tire structure.

DESCRIPTION OF THE REFERENCE SYMBOLS AND SIGNS

b: fine-strip-shaped belt member pieces, b1: distal end having acuteangle, C: reinforcing cord, D: building drum, E: support base for movingbuilding drum, T: tire, 1: belt edge tape, 2: inner liner, 3: tread, 4:side wall, 5: rim strip, 6: carcass layer, 7: belt layer, 7 a:lower-layer belt, 7 b: upper-layer belt, 8: bead body, 8 a: bead core, 8b: bead filler, 9: reinforcing layer, 10: extruder, 11: body, 12: headportion, 13: die, 14: drive motor, 15 a, 15 b: upper and lower pressrollers, 16 a, 16 b: arm members, 17 a, 17 b: pressing drive means, 20:moving means

1. A method of adhering belt edge tapes made of a rubber material whichare interposed between upper and lower layer belts containing inclinedreinforcing cords therein to side edge portions of the lower layer beltafter adhering to an outer peripheral surface of a building drum duringone step of tire building, wherein in adhering the belt edge tape to theboth respective side edge portions of the lower layer belt on the outerperipheral surface of the building drum by supplying the belt edge tapetoward the outer peripheral surface of the building drum along with therotation of the building drum by a supply device which faces thebuilding drum in an opposed manner and by pressing the belt edge tape tothe building drum using a press roller on a leading side as viewed froma position where the belt edge tape is supplied in the rotationaldirection of the building drum along with the supplying of the belt edgetape, the building drum is rotated in the direction opposite to thedirection that acute-angled distal ends which are formed by the inclinedreinforcing cords of the lower lay belt and side edge of the lower layerbelt are facing.
 2. A method of adhering belt edge tapes according toclaim 1, wherein the method uses an extruder which extrudes the beltedge tape having a predetermined cross-sectional shape toward thebuilding drum as the supply device.
 3. A method of adhering belt edgetapes according to claim 1 or 2, wherein the belt is formed of a beltmember which is obtained by obliquely cutting a belt-use strip-shapedmaterial made of a rubber material in which a plurality of reinforcingcords is embedded in parallel with each other and by arranging andbonding a large number of fine-strip-shaped belt member pieces which areformed by cutting in a state that the cords are arranged in theinclination direction, in adhering the belt edge tape to both respectiveside edge portions of the belt adhered to the building drum, thebuilding drum is rotated in the direction that end portions of the beltmember pieces on the side edge portion of the belt which constitutes atape adhering side are positioned on a trailing side in the rotationaldirection of the building drum.
 4. A method of adhering belt edge tapesaccording to any of claims 1 and 2, wherein interposing the belt edgetapes between the lower layer belt and the upper layer belt by adheringthe upper-layer belt on the belt edge tapes and the lower-layer beltafter adhering the belt edge tapes on the lower-layer belt.
 5. A methodof adhering belt edge tapes according to claim 3, wherein interposingthe belt edge tapes between the lower layer belt and the upper layerbelt by adhering the upper-layer belt on the belt edge tapes and thelower-layer belt after adhering the belt edge tapes on the lower-layerbelt.